Station selector for radioreceivers



F. KOCH 3 STATION SELECTOR FOR RADIORECEIVERS Filed Nov. 2, 192'! Jwerzfon Patented Sept. 4, 1934 UNITED STATES P.

TENT

Application November 2, 1927, Serial No. 230,646 In Germany September 24, 1927 22 Claims. (Cl. 25040) This invention relates to selective wireless refor live different capacity settings; it might, ceiving apparatus employing one or more oscilhowever, be constructed for more or less settings latory circuits tuned by means of variable conthan five. The movable member of each condensers, and the object of the invention is to denser unit may be frictionally or otherwise held 5 provide a new and improved construction and in its adjusted position and each unit when once 0 arrangement of parts in a condenser which will adjusted for tuning the circuit to a given wave enable a number of condenser settings to be length is intended to remain so adjusted as long made for tuning a circuit into resonance with as it is desired to have such unit adjusted for tuna number of transmitting stations operating at ing in such particular station. When, however,

10 predetermined wave lengths, and such settings to an alteration in any condenser setting or adjustbe preserved after having been once made, so as ment is desired, it can be made at any time. to be instantly available for tuning in any one The adjustment of each condenser is elf-acted by of the stations represented by the settings by a coupling its hub, by tightening the set-screw it, simple switching operation, i. e., without fishto the shaft b whereupon, by rotating shaft 12,

15 ing or searching. the rotor may be adjusted with relation to the The invention consists essentially in the emstator 6 until the desired capacity value is obployment of several adjustable condensers tained. The screw it is then loosened so that mounted in one assemblage in combination with shaft 12 is uncoupled from the rotor of the conmeans for selecting one of I the number for condenser unit which has been set or adjusted and nection to the receiving apparatus so as to form which will remain so set or adjusted, and withpart of the tuned receiving circuit. out being affected by any subsequent turning Two embodiments of the invention will be movements of shaft 2), unless and until it hereinafter described, by Way of example, with again connected to the shaft by its set-screw h. reference to the accompanying drawing, said This condenser is mounted in a radio ap- 25 embodiments being shown in top elevation, paratus, as shown, for example, in a receiver R, partly in section, the one in Fig. l, the other in for tuning the same into resonance with the Fig. 2, and also showing diagrammatically a cirstations selected. A switch is, which is shown as cuit to be tuned thereby. a lever-switch, but might be a push-button- The embodiment shown in Fig. 1 will be first switch, serves for selectively connecting any one 30 described. of the conductors i, 2', 2' i i from the stators As mentioned above the condenser comprises of the condenser units with the receiving circuit,

several adjustable condensers, five being shown While a conductor 2' connects the shaft b, and in the present instance and denoted A, B, C, D, E, consequently all the rotors of the condenser respectively. These are mounted in a frame :1, units, in common with said circuit.

35 made of insulating material. A shaft b jour- Fig. 2 shows another form of construction by naled in this frame serves as a current conducway of example, in which the condenser units tor. The shaft b carries a milled knob c on one A, B, C, D, E are complete in themselves, end and its other end rests on a center pivot d. i. e., separate devices being provided for adjust- Each of these several condensers comprises a ing each set of rotor plates. As shown, the

stationary member consisting of a set of stator casing is sub-divided into a series of compartplates e fixed on the frame a and an adjustable ments by partitions Z of insulating material ear-- member consisting of a set of rotor plates ried by rods or bars m. Each set of stator plates mounted on the shaft b.v The sets of plates e e is fixed on a partition Z, and the coacting set of the respective condenser units A, B, C, D, E of rotor plates f are carried by a shaft piv- 45 are insulated from one another by insulating otally mounted in said partition. Levers 0, one

partitions or disks 9 and are sufficiently spaced for each set of plates f, have projecting handles to avoid undesirable reactions or intercapacity p, and one of these levers o is provided for adefiects- Each set of rotor plates f on the shaft b, justing the rotor plates of all the condenser is loose on said shaft and adapted to be coupled units except the unit A, a knob or dial r being 50 to or uncoupled from said shaft 19 independently provided on the shaft of the rotor plates of of the other sets, this being effected by means of unit A for adjusting the rotorplates of this a clamping or friction means, constructed in any unit. As in the construction shown in Fig. l convenient manner, such, for example, as a setthe movable members of the adjusted units may screw h. 1 be frictionally or otherwise held in adjusted 55 The arrangement shown in Fig. 1 is intended position, and conductors from the rotors of all the units are provided for connecting the same with one of the oscillation circuit to be tuned, while ."vitch lever q serves for operating a switch or member c" connecting any one of a se""s switch points i 2', i i "5 forming the terminals conductors leading from the sets of stator plates of the respective condenser l the other side of said circuit. use of i lo" or dial 1 i r tuning condenser unit A per this condenser unit to adjusted by a conveniently arranged adjustelement which is mounted on the outer end of the shaft of the unit A which is extended through open ng 8 in the front panel P to the outside of the rec iver casing, for the use Us. the unit A as a general purpose condenser, that is, for tuning the receiver to any station it is capable of receiving, while the levers 0 may be on the inside of the panel P, if desired, as these used to set units B, C, D, E to tune in certain stations and, therefore, need be operated only when chang ng the setting of any of these latter-nanied units.

The lever q, as shown, is mounted to rotate on the shaft of the condenser unit A on the outside of the pa=-el and carries the switch arniq which in turn carries a contact member or which extends to the interior side of the panel through a slot o in the panel in which it is movable through its waking are so as to sweep over the contacts i 5 to cut any of the pro-set condenser units B'-E or the continuously variable condenser unit A into or out of the radio circuit. The series of contacts i -i mounted on a switchboard or plate P of ng material arranged at the front of the condenser frame between the continuously variaole condenser unit A and the panel P. With this arrangement it will be seen that the individual condenser units B-E may be adjusted by means, namely, their adjusting or setting 0 located. on the inside of the panel, to pro-set said condensersto proper values for pretuning the circuit to different selected working frequencies, while the condenser unit may be adjusted by means of its knob or dial r'for independently tuning the circuit to any frequency throughout entire frequency range or any desired part thereof. It will also be seen that the switch contact member (1 is so arranged as to form with the contacts i -F a selector switch the contact members of which are operably engageable on the inside of the panel While the movable member thereof, he contact member q mentioned, is movable for operable engagement with its coacting contacts i by means located on the outside, i. e., the front, of the panel P. The switch arm 61' is extended beyond the contact member (1 which may cooperate with suitable indicator on or visible at th outer face of the panel so that the operator may tell at a glance the position to which the switch movable to bring the contact member (1 into engagement with any of the contacts i -2' as well as to tell which contact of series the contact member may be in en agement with at any particular time when the switch is in use.

I claim:-

1. A multi-unit variable radio condenser comrising a frame, a rotary shaft journaled on the rarne, a plurality of independent condenser. units, each consisting of relatively stationary and adjustable members respectively fixed. to the frame and loosely mounted relative to the shaft,

means for independently coupling the adjustable members of the units to the shaft and uncoupling the same therefrom, whereby the adjustable members of the respective units may be adjusted by rotation of the shaft for presetting the units for tuning a radio circuit into resonance with transmitting stations of different frequencies, and switching means for selectiveli connecting any of said individual units with or disconnecting it from the radio circuit without disturbing the setting of the individual units.

2. A multi-unit variable radio condenser comprising a frame, a shaft journaled on the frame, a plurality of condenser units each comprising relatively stationary and adjustable members respectively supported by the frame and the shaft, the said adjustable members being normally loose relative to the shaft and adapted to be fixed thereto for adjustment thereby, whereby the movable members of the units may be independently adjusted for individually pre-setting the respective units for tuning a radio circuit into resonance with transmitting stations of different frequencies, means for independently connecting the movable members of the respective units to and disconnecting the same from the shaft, and switching means for selectively connecting any of said individual units with or disconnecting it from the radio circuit without disturbing the setting of the individual units.

3. In a. radio tuner, 21. frame of insulated material, a gang of air condensers mounted in cascade on said frame, each comprising a stator and a rotor, partitions of insulated material on the frame disposed between and separating the individual condensers from each other, a single means for separately and independently adjusting the rotors of the respective condensers, whereby the condensers may be individually preset for tuning a radio circuit into resonance with a like number of individual transmitting stations operating on different wave lengths, and switching means operable to selectively connect any of the pro-set condenser units with a radio circuit.

4. A tuner for radio apparatus comprising a frame, a shaft journaled in the frame, a plurality of sets of stator elements on the frame, a plurality of sets of coacting rotor elements loosely mounted relative to the shaft, coupling means whereby eachset of rotor elements may be coupled to the shaft for adjustment thereby to a predetermined angular position and then released therefrom, whereby the rotors may be independently'adjusted by the shaft for setting actions to tune a radio circuit to different frequencies, and switching means for connecting any of the sets of rotors and stators to a radio circuit.

5. A tuner for radio apparatus comprising a frame, a shaft journaled in the frame, a p1urality of sets of stator elements on the frame, a,

plurality of sets of coacting rotor elements loosely mounted relative to the shaft, coupling means whereby each set of rotor elements may be coupled-to the shaft for adjustment thereby to a sets of rotor elements independently of one another to the other side of said radio circuit.

6. A tuner for radio apparatus comprising a frame of insulating material, partitions on the frame separating the same into spaces, a shaft aled on the frame, a set of stator elements led the frame in each of said spaces, a set of rotor elements on the shaft in each of said s aces for coaction with the stator elements therein, the sets of rotor elements being loosely mounted relative to the shaft, means for independently connecting the same to the shaft, whereby the sets of rotor elements may be adjusted to diiferent angular positions for coaction with the stator elements to tune a radio circuit to diiferent frequencies, means for connecting all the stator elements to one side of a radio circuit, and a switch device for connecting the sets of rotor elements independently of one another to the other side of said circuit.

7. A to; for radio circuits comprising a gang of tuning units, an adjusting element common to said units normally 0 erably disconnected therefrom, means for separately coupling said sting element to each unit, wl ereby any i the may be adjusted independently 01 the other units, and means for selectivelyconneoting any of the tuning units into a radio circuit.

S. A tuner for radio circuits comprising a gang of variable tuning condensers, an adjusting clement common to the movable elements of the condensers normally operably disconnected therefrom, means for separately coupling said adjusting element to the movable el ments of the condensers, whereby any condenser of the gang may be adjusted for tuning a radio circuit to a predetermined frequency independently of the other condensers, and means for selectively connecting any of the condensers into a radio circuit.

9. A tuner for radio circuits comprising a gang of tu ng units, an adjusting element common to sa units normally operably disconnected therefrom, means for separately coupling said adjusting element to each unit, whereby any unit of the gang may be adjusted independently of the other units, a switch for independently and selectively connecting any of the tuning units of the gang ith a radio circuit.

19. A tuner for radio circuits comprising a gang of variable tuning condensers, an adjusting element common to the movable elements of the condensers normally operably disconnected therefrom, means for separately coupling said adjusting element to the movable elements of the condensers, whereby any condenser of the gang may be adjusted for tuning a radio circuit to a predetermined frequency independently of the other condensers, and a switch for independently and selectively connecting any of the condensers of the gang with a radio circuit.

ll. A tuner for radio circuits comprising a frame, a rotary shaft journaled on the frame, a lity of condenser units carried by the frame each consisting of a stator and a rotor, the rotors of said units being normally operably disconnected from said shaft, coupling means for coupling each rotor to and uncoupling it from the shaft, w ereby the rotors may be independently adjusted by the shaft to predetermined angular degrees with relation to their stators for setting said units for respectively tuning a radio circuit to different frequencies, and switching capacitor means for connecting any of the individual units into the radio circuit.

12. A tuner for radio circuits comprising an insulated frame, insulating partitions separating said frame into a plurality of spaces, a shaft journaled on the frame, a plurality of condenser units disposed in said spaces, each condenser unit consisting of a stator and a rotor, the rotors of 5 id units being normally opcrably disconnected from said shaft, coupling means for coupling each rotor to and uncoupling it from the shaft, whereby the rotors may be independonly adjusted by the shaft to predetermined angular degrees with relation to their stators for setting said units for respectively tuning a radio circuit to different frequencies, and switching means for connecting any of the individual units into the radio circuit.

13. A tuner for radio circuits comprising a plurality of tuning instruments embodying relatively stationary and movable elements, a rotatable shaft common to and normally operably disconnected from the movable elements of said instruments, coupling means whereby the movable elements of the instruments may be independently coupled to the shaft for adjustment thereby to a predetermined tuning position and then opcrably released therefrom, for setting said instruments for respectively tuning a radio circuit to different frequencies, and switching means for connecting any of the tuning instruments to the radio circuit.

1 In a radio tuner, a gang condenser comp: pg 2. frame, a series of unitary air condensers mounted in cascade on the frame and each embodying a stator and a rotor, a shaft common to the series of condensers, coupling means for connecting the shaft with the rotor of any of the condensers, whereby said rotor may be adjusted relatively to its stator independently of the rotors of the other condensers, and switching means for selectively cutting any of said condensers into or out of a radio circuit.

15. In a radio tuner, a panel, a tuning device comprising a gang of individual variable air condensers disposed on one side of the panel, each condenser embodying stator capacitor plates and rotor capacitor plates, an adjusting element common to said condensers nor mally cperably disconnected. therefrom, said elementhaving'an operating portion disposed on the opposite side of the panel from the condensers, means for separately and independently connecting said adjusting element to the rotor plates of the respective individual condensers, whereby the condensers may be individually adjusted to different frequency settings, and a switch device including an operating element also disposed on the opposite side of the panel from the condensers for selectively connecting any of the condensers with and disconnecting the same from a radio circuit.

16. In a tuner for radio circuits, a tuning device comprising a plurality of individual variable air condensers each embodying a stator and a rotor, a single means normally operably disconnected from but having a cooperative coupling connection with the condenser rotors for separately and independently adjusting the rotors of the respective condensers with relation to their stators, whereby any condenser of the gang may be individually adjusted for tuning a radio circuit to a predetermined frequency independent of any other condenser of the gang, and a switch 156 device for cutting any of the condensers into or out of a radio circuit.

17. An electrical condenser comprising a plurality of variable condenser units, each independent of the others, one of said units being continuously variable and having an operating shaft, means associated with each of the other condenser units for independently adjusting said unit to vary its capacity, whereby said other units may be individually set for tuning a circuit when connected therewith into resonance with a corresponding number of stations of different frequencies, and a switch device including a movable member mounted concentric with the operating shaft of the continuously variable con-- denser unit for connecting any of the condenser units into a radio circuit independently of the others.

18. In a tuner for radio circuits, a plurality of separate and independent condenser units adjustable for pretuning a circuit to different working frequencies, means for independently adjusting said condenser units, a continuously variable condenser unit including a rotatable member having an adjusting shaft, switching means for selectively cutting said units into or out of the radio circuit including contacts arranged, concentric with said adjusting shaft and a rotary contact member mounted coaxially with said shaft for engagement with said contacts, and operating members for independently shifting said contact member and the rotatable member of said continuously variable condenser.

19. In a tuner for radio circuits, a plurality of variable condenser units arranged one in rear of the other and each consisting of relatively fixed and adjustable capacitor members, means upon each condenser unit in rear of the first unit of the series for relatively adjusting the capacitor members thereof independently of the capacitor members of the other condenser units to vary the effective capacity of said unit, whereby said units may be pre-set to tune the circuit to diiferent working frequencies, the said first unit of the series being continuously variable for tuning the circuit over a desired frequency range and having an operating shaft for adjusting the movable capacitor member thereof, means connected with the shaft of the first unit for operating the same, and switching means concentric with the shaft of the first unit for cutting said condensers into the circuit.

20. In a tuner for radio circuits, a gang condenser comprising a series of individual condenser units arranged one in rear of the other and each embodying a stator and a rotor, the rotor of one of the end units of the series having an adjusting shaft, means upon the rotor of each of the other units of the series extending outward radially with relation to its axis for adjusting said rotor to vary the capacity of the unit, a switchboard arranged adjacent to said end unit and in advance of which the adjusting shaft of said unit extends, switch contacts on the switchboard concentric with said shaft and connected with the respective condenser units, a rotary switch member mounted coaxially with said shaft and engageable with said contacts for selectively cutting the condenser units in or out of a radio circuit, and means uniting said units and switchboard in a unitary structure.

2'1. In a tuner for radio circuits, a gang condenser comprising a frame structure, a series of adjustable condenser units mounted on the frame structure, each unit being adjustable to vary its setting without varying the setting of any other unit, a switchboard carried by the frame structure, an additional variable condenser unit carried by the frame structure between the switchboard and said series of condenser units, said additional unit having an adjusting shaft extending in advance of the switchboard, a hollow shaft mounted on and rotatable about said adjusting shaft, an operating element for adjusting the adjusting shaft, switch contacts on the switchboard respectively connected with said units, and a switch connected with the hollow shaft and movable thereby for coaction with said contacts to selectively connect any of said units with a radio circuit.

22. In a tuner for radio circuits, a gang of variable condenser units, comprising a plurality of pretuning units with means for respectively presetting said units for selectively tuning a radio circuit to different working frequencies and a continuously variable unit adjustable without disturbing the setting of any of the aforesaid units for tuning the circuit throughout a desired frequency range, a control shaft operable for adjusting the continuously variable condenser unit, and switching means arranged at one end of the gang and comprising contacts concentric with said shaft and connected to the units of the gang, and a switch member mounted coaxially with said shaft and engageable with the contacts for selectively connecting the units of the gang with the circuit.

FRITZ KOCH. 

